1. Technical Field
The present invention concerns a rudder blade for a ship and a ship having at least one rudder blade according to the invention.
2. Description of the Related Art
If the flow along the hull of a ship as it moves is considered, it can then be clearly seen that, at a tapering stern of the ship, the flow does not extend exactly parallel to the line of the keel of the ship but follows the configuration of the stern of the ship.
A rudder of conventional design, that is to say expressed in simple terms a flat plate, which is mounted laterally displaced from the line of the keel in the stern region of the ship and is oriented in the zero-degree position exactly parallel to the line of the keel would therefore have an afflux flow thereagainst at an inclined angle and thus gives rise to a flow resistance. That flow resistance signifies higher fuel consumption and thus a higher level of environmental pollution or with the same fuel consumption or the same engine power a low speed and thus a longer travel time and thus in turn higher fuel consumption and more severe environmental pollution.
It is known from U.S. Pat. No. 5,415,122 for a rudder blade to be adapted to a propeller-generated flow. In that case the flow directions produced by the propeller are taken into consideration and the rudder suitably adapted in a multiplicity of profiles in the chord direction. For example, Table 1 of that publication specifies a reduction in an angle of the rudder blade with an increasing height (Y-position) of the respective profile, starting from the axis of the propeller disposed in front thereof. That specific configuration of a rudder blade also takes in account the effects due to turbulence due to the rudder.